And I'm Melissa Block. A measure to expand background checks for gun purchases has been defeated in the Senate. The compromise amendment crafted by Democrat Joe Manchin and Republican Pat Toomey would have required checks on Internet sales and at gun shows. Not long after the Senate voted, President Obama delivered a defiant speech in the White House Rose Garden.

PRESIDENT BARACK OBAMA: There were no coherent arguments as to why we wouldn't do this. It came down to politics.

BLOCK: After the shootings in Newtown, Connecticut, President Obama called for an assault weapons ban, a limit on the size of ammunition magazines, and he called for expanded background checks. Well, today, none of those proposals got through the Senate.

Joining us now from the Capitol is NPR's Ailsa Chang. And, Ailsa, there were a whole series of votes on these amendments, and the proposal everyone's been focused on was this proposal to expand background checks. It was the first vote, and it went down. What happened?

AILSA CHANG, BYLINE: Well, as people have been expecting in the last day or so, that proposal totally failed. It needed 60 votes under the rules the Senate adopted, and it only got 54. Right after, though, you could actually hear people watching from the gallery suddenly yell shame on you to the senators. And President Obama actually echoed that scolding right in the Rose Garden later.

OBAMA: So all in all, this was a pretty shameful day for Washington.

CHANG: The background checks provision, as you said, was a bipartisan plan sponsored by Senator Manchin of West Virginia and Republican Pat Toomey of Pennsylvania, and it would have extended background checks to online sales and gun shows. But over the last day or two, it was looking less and less likely that the Democrats would get those 60 votes.

In fact, today, more than an hour before the Senate even began to vote, Republican Senator John McCain from Arizona was already on the floor saying to Manchin and Toomey: I'm proud of you. You guys did good. Maybe we'll try again in the future.

SENATOR JOHN MCCAIN: What they have tried to do today, I think, is an act that should be appreciated by those of us who, many times, avoid taking the tough decisions. And I think they're an example to all of us.

CHANG: McCain was one of the few Republicans who did support the Manchin-Toomey amendment. It's important to understand that this amendment was the key vote today because the main bill that Senate Majority Leader Harry Reid is trying to push through contains a background checks provision that no Republicans currently support. So this Manchin-Toomey compromise was a way to make that overall Senate package more palatable to the Republicans and conservative Democrats.

BLOCK: And in the end, as you say, Ailsa, that didn't work for Republicans voting yes on the expansion, five Democrats joining the Republicans to vote it down. What were some of the reasons that senators gave you for why this proposal failed?

CHANG: Well, if you ask Senator Manchin, it was because gun rights groups were spreading false information about the amendment. For example, the proposal would have exempted private transfers of guns, say, between family members. But Manchin says the NRA has been telling its members the proposal would criminalize private transfers between friends, family and neighbors. And then there was this other concern, that more background checks means the government will have access to more records of who owns guns, and that could one day lead to a national registry of gun owners. Here's Republican Senator Chuck Grassley of Iowa.

SENATOR CHUCK GRASSLEY: The government knowing where guns are is a bad thing and a violation and a slippery slope of compromising the Second Amendment.

BLOCK: Well, Senator Grassley and some other Republicans were pushing some of their own proposals today. Why don't you tell us about some of those?

CHANG: Yeah. He and other Republican senators are pushing a broad Republican amendment that also failed. It would have increased penalties for gun trafficking and increase resources to prosecute people who try to get around background checks. It would have also tried to improve the background check's database by including more people who've been judged to have mental health problems.

Some amendments would have even expanded gun rights. There was a Republican amendment that failed that would have made any state-issued permit to carry a concealed weapon valid in any other state. And, of course, there were democratic amendments like the assault weapons ban and a limit on ammunition magazines, and those failed too.

After the votes, Harry Reid made it very clear he is not giving up. In fact, he had voted against the Manchin-Toomey amendment so that he'd be permitted under Senate rules to bring up the amendment again and again and again if he'd like. Democratic Senator Chuck Schumer of New York also chimed in after the votes today and said: Look, things can happen very, very quickly in Washington. Look at what's happening with same-sex marriage. And so the message today, after all was said and done, was there's more to come.